Iron Mountain Incorporated
DE ˙ DB ˙ US46284V1017
111,85 € ↑2,30 (2,10%)
2026-06-05
DEL PRIS
SecurityDE:I5M / Iron Mountain Incorporated
InstitutionBaird Financial Group, Inc.
Latest Disclosed Ownership42,707 shares
Latest Disclosed Value $ 4,362,128
Baird Financial Group, Inc. reports 6.94% decrease in ownership of I5M / Iron Mountain Incorporated

On May 14, 2026 - Baird Financial Group, Inc. filed a 13F-HR form disclosing ownership of 42,707 shares of Iron Mountain Incorporated (DE:I5M) valued at $3,791,527 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 45,891 shares of Iron Mountain Incorporated. This represents a change in shares of -6.94% during the quarter. The current value of the position is $4,776,778 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-14 2026-03-31 13F IRON MTN INC DEL COM 46284V101 42,707 -3,184 -6.94 4,362 14.61 0.0037
2026-02-13 2025-12-31 13F IRON MTN INC DEL COM COMMON 46284V101 45,891 -747 -1.60 3,807 -19.94 0.0059
2025-11-13 2025-09-30 13F IRON MOUNTAIN INC COMMON 46284V101 46,638 -2,032 -4.18 4,754 -4.77 0.0076
2025-08-13 2025-06-30 13F IRON MTN INC DEL COM COMMON 46284V101 48,670 -13,640 -21.89 4,992 -6.88 0.0088
2025-05-15 2025-03-31 13F IRON MTN INC DEL COM COMMON 46284V101 62,310 -3,196 -4.88 5,361 -22.14 0.0103
2025-02-14 2024-12-31 13F IRON MOUNTAIN INC COMMON 46284V101 65,506 826 1.28 6,885 -10.41 0.0132
2024-11-14 2024-09-30 13F IRON MOUNTAIN INC COMMON 46284V101 64,680 2,229 3.57 7,686 37.33 0.0149
2024-08-14 2024-06-30 13F IRON MOUNTAIN INC COMMON 46284V101 62,451 137 0.22 5,597 11.96 0.0116
2024-05-14 2024-03-31 13F IRON MOUNTAIN INC COMMON 46284V101 62,314 9,457 17.89 4,998 35.15 0.0105
2024-02-14 2023-12-31 13F IRON MOUNTAIN INC COMMON 46284V101 52,857 -42,057 -44.31 3,699 -34.46 0.0084
2023-11-13 2023-09-30 13F IRON MOUNTAIN INC COMMON 46284V101 94,914 14,470 17.99 5,643 23.46 0.0154
2023-08-11 2023-06-30 13F IRON MOUNTAIN INC COMMON 46284V101 80,444 22,388 38.56 4,571 48.81 0.0121
2023-05-15 2023-03-31 13F IRON MOUNTAIN INC COMMON 46284V101 58,056 -1,311 -2.21 3,072 153,450.00 0.0076
2023-02-13 2022-12-31 13F IRON MOUNTAIN INC COMMON 46284V101 59,367 12,027 25.41 3 -99.90 0.0078
2022-11-15 2022-09-30 13F IRON MOUNTAIN INC COMMON 46284V101 47,340 1,368 2.98 2,081 -7.06 0.0061
2022-08-08 2022-06-30 13F IRON MOUNTAIN INC COMMON 46284V101 45,972 184 0.40 2,239 -11.71 0.0062
2022-05-13 2022-03-31 13F IRON MOUNTAIN INC COMMON 46284V101 45,788 1,723 3.91 2,536 10.02 0.0063
2022-02-09 2021-12-31 13F IRON MTN INC NEW COM COMMON 46284V101 44,065 -5,696 -11.45 2,305 6.61 0.0054
2021-11-12 2021-09-30 13F IRON MTN INC NEW COM COMMON 46284V101 49,761 -2,712 -5.17 2,162 -2.66 0.0055
2021-08-11 2021-06-30 13F IRON MTN INC NEW COM COMMON 46284V101 52,473 -1,523 -2.82 2,221 11.16 0.0058
2021-05-13 2021-03-31 13F IRON MTN INC NEW COM COMMON 46284V101 53,996 18,821 53.51 1,998 92.67 0.0056
2021-02-11 2020-12-31 13F IRON MTN INC NEW COM COMMON 46284V101 35,175 35,175 1,037 0.0031
2020-11-12 2020-09-30 13F IRON MOUNTAIN INC COMMON 46284V101 0 -10,451 -100.00 0 -100.00
2020-10-22 2020-06-30 13F/A-1 IRON MOUNTAIN INC COMMON 46284V101 10,451 -10,712 -50.62 273 -45.83 0.0010
2020-08-14 2020-06-30 13F IRON MOUNTAIN INC COMMON 46284V101 30,515 9,352 921 1,825.2128
2020-05-14 2020-03-31 13F IRON MOUNTAIN INC COMMON 46284V101 21,163 1,249 6.27 504 -20.63 0.0023
2020-02-14 2019-12-31 13F IRON MOUNTAIN INC COMMON 46284V101 19,914 3,837 23.87 635 21.88 0.0023
2019-11-14 2019-09-30 13F IRON MTN INC NEW COM Common 46284V101 16,077 2,902 22.03 521 26.46 0.0021
2019-08-14 2019-06-30 13F IRON MOUNTAIN INC COMMON 46284V101 13,175 863 7.01 412 -5.72 0.0016
2019-05-14 2019-03-31 13F IRON MOUNTAIN INC COMMON 46284V101 12,312 2,287 22.81 437 34.46 0.0026
2019-02-14 2018-12-31 13F IRON MOUNTAIN INC COMMON 46284V101 10,025 840 9.15 325 2.85 0.0022
2018-11-13 2018-09-30 13F Iron Mountain COMMON 46284V101 9,185 1,426 18.38 316 16.18 0.0020
2018-08-13 2018-06-30 13F IRON MOUNTAIN INC COMMON 46284V101 7,759 7,759 272 0.0018
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.